The field of this invention is that of diesel fuel filter systems and the invention relates more particularly to a system which is adapted for use in passenger automobiles.
With the present energy crises extending world-wide, the use of diesel-powered passenger automobiles is rapidly increasing. As a result, diesel engines have to be adapted for more trouble-free operation by drivers who may not provide routine maintenance such fuel filter replacement and the like with the same degree of care as professional drivers and who may be unable to cope with problems such as fuel filter clogging which may occur. At the same time, it would be desirable to lower the cost of diesel-powered automobiles to reach the larger popular market which is becoming interested in such vehicles and to adopt the diesel-powered automobiles to incorporate the various, power-operated automobile convenience features to which the popular market has become accustomed. In this regard, it is found that although diesel fuel as manufactured is intended to have low boiling point constituents removed from the fuel, paraffin residues and the like which may remain in the fuel can solidify in the fuel in the fueltank or filter housing when diesel powered automobiles or other equipment stand idle during cold weather. Then, when operation of the engine is initiated, such solidified components of the fuel tend to clog the filter as the fuel passing to the engine is filtered for removing extraneous contaminant particles and the like. In many cases such filter-clogging solidified fuel components will be returned to liquid state and passed through the filter to the engine as engine warm up gradually takes place. Frequently, however, such clogging will sufficiently reduce fuel flow so that engine performance is adversely affected during the initial period of engine operation. This can result in considerable driver inconvenience particularly where routine filter replacement may have been disregarded or where the filter clogging is not recognized or understood due to driver inexperience.
It will be desirable to be able to avoid such cold weather filter clogging particularly if such an improvement could be achieved at reasonable cost in a manner which would not involve undue drain on the electrical power supply capacity of the automobile.
It is an object of this invention to provide a novel and improved diesel fuel filter system; to provide such a diesel fuel filter system which is free from cold weather filter clogging; to provide such a system which utilizes low cost components adapted to be incorporated in an otherwise conventional fuel filter system; to provide such a filter system which is operable without excessively loading the electrical power supply capacity of the automobile or other diesel-powered equipment; and to provide such a system which can be used without risk of fuel overheating and the like.